3rd Generation Partnership Project 3GPP is a collaboration between groups of telecommunications associations that have joined to define globally applicable third-generation (3G) mobile phone system specifications (e.g., within the scope of the International Mobile Telecommunications-2000 project of the International Telecommunication Union (ITU)) based on evolved Global System for Mobile Communications (GSM) specifications and encompassing radio, core network and service architecture. Among several other standards within 3GPP, Long Term Evolution (LTE) is a standard within the mobile network technology arena.
In the evolution of LTE-compliant networks, relay nodes are being deployed to help extend network coverage to user equipment and to improve cell-edge bandwidth. Unlike other network devices, such as evolved nodeBs (eNB), Mobility Management Entity (MME), etc., which operate under the control of operator-controlled physical locations, relay nodes tend to be placed closer to the user equipment in physically more accessible or vulnerable locations and operate more independently. As a result, relay nodes are prone to certain new security threats and attacks (e.g., man-in-the-middle attacks, relay node impersonations attacks, etc.) that are not present in other network devices such as eNB or MME. Moreover, relay nodes are often utilized to promote communication between user equipment and the network devices.